Fourth-Generation Programming Language (4GL) is a computer programming language is  visualised as a refinement of the style of languages classified as Third-Generation Programming Language (3GL).As each of the programming language generations aims to provide a higher level of abstraction of the internal computer hardware details, making the language more programmer-friendly, powerful and versatile.

While the definition of 3GL has changed over time, it can be typified by operating more with large collections of information at once rather than just focusing on bits and bytes. Languages claimed to be 4GL may include support for database management, report generation, mathematical optimization, GUI development, or web development. Some researchers state that 4GLs are a subset of domain-specific languages.The concept of Fourth-Generation Programming Language was developed in late 1970s through the 1990s, overlapping most of the development of 3GLs. While 3GLs like C, C++, C#, Java, and JavaScript remain popular for a wide variety of uses, Fourth-Generation Programming Language as originally defined found narrower uses some of the most advanced 3GLs like Python, Ruby, and Perl combine some of 4GLs abilities within general-purpose of 3GL environment. Also, libraries with 4GL-like features have been developed as add-ons for most popular 3GLs. This make bit difficult to distinguis 4GLs and 3GLs.With respect to type here you can find some examples of Fourth-Generation Programming Language

General use / versatile
  • Accelerator (Productivity)
  • Accell/SQL (4GL) from Unify Corporation.
  • Clarion
  • Clipper
  • CA-Telon 4GL Cobol/PLI generator
  • Cognos PowerHouse 4GL
  • DataFlex
  • Forté TOOL (transactional object-oriented language)
  • FOCUS from Information Builders Inc.
  • Visual FoxPro
  • Genero (Four J’s)
  • GeneXus (Knowledge-based Multi-Platform Development Tool)
  • IBM Rational EGL (Enterprise Generation Language)
  • Omnis Studio SDK
  • OutSystems (Productivity/PaaS)
  • Panther
  • PowerBuilder
  • Perl
  • PHP
  • Python
  • Ruby
  • Oracle Application Development Framework
  • DEC RALLY
  • SheerPower4GL (Microsoft Windows only)
  • SQLWindows/Team Developer
  • Visual DataFlex (Microsoft Windows only)
  • WinDev
  • Unix Shell
  • XBase++
  • Manage (SDS Sigma series mainframes)
Database query languages
  • FOCUS
  • 4D QL
  • Informix-4GL
  • OpenEdge ABL
  • OpenROAD (Ingres 4GL)
  • Ramis
  • SQL
Report generators
  • Tally Definition Language(TDL): This is domain specific language for ERP & Accounting from Tally solutions Pvt Ltd
  • BuildProfessional
  • LIRC
  • NATURAL
  • Oracle Reports
  • Progress 4GL Query/Results
  • Quest
  • RPG-II
Data manipulation, analysis, and reporting languages
  • Ab Initio
  • ABAP
  • Aubit-4GL
  • Audit Command Language
  • Clarion Programming Language
  • CorVision
  • Culprit
  • ADS/Online (plus transaction processing)
  • Easytrieve
  • FOCUS
  • GraphTalk
  • IDL
  • MAPPER (Unisys/Sperry) now part of BIS
  • MARK-IV (Sterling/Informatics) now VISION:BUILDER of CA
  • Simulink a component of MATLAB
  • NATURAL
  • Nomad
  • PL/SQL
  • SAS
  • SPSS
  • SQL PL
  • SQR
  • Stata
  • Synon
  • Wolfram Language
  • XBase++
  • Xquery Backward compatible with SQL and forward compatible with XML data sources.
GUI creators
  • 4th Dimension (Software)
  • MATLAB’s GUIDE
  • Omnis Studio
  • OpenROAD
  • Progress 4GL AppBuilder
  • SuperTalk
  • Transcript (LiveCode)
  • XUL Can be used with Xquery to create web GUI database applications quickly.
  • Visual DataFlex
Database-driven GUI application development
  • Action Request System
  • C/AL
  • Genexus
  • SB+/SystemBuilder
  • Progress Dynamics
  • Unify VISION
Screen painters and generators
  • SB+/SystemBuilder
  • Oracle Forms
  • Progress 4GL ProVision
Web development languages
  • ActiveVFP
  • CFML
  • LANSA
  • Wavemaker open source, browser-based development platform for Ajax development based on Dojo, Spring, Hibernate
  • OutSystems